There are many references in prior art suggesting extraction with liquid and supercritical fluids, wherein solids are placed in static environment. Fluids are pumped through a static mass of solids to dissolve the extractables.
The prior art describing such procedures includes U.S. Pat. Nos. 4,156,688; 4,328,255; 4,466,923; 4,493,854; and 4,495,207.
A related procedure for extraction is described in application Ser. No. 732,362 filed May 8, 1985 now U.S. Pat. No. 4,683,063.